1. Field of the Invention
The present invention relates to an image processing method and device, and more particularly, to an image processing method and device for filtering out the detected mosquito noise(s) near an edge in an image.
2. Description of the Prior Art
In the technical field of image processing, MPEG (Moving Picture Experts Group) and/or JPEG (Joint Photographic Experts Group) compression is commonly utilized in applications that encode, decode, transmit, store, or play images. Typically, DCT (Discrete Cosine Transform) is performed on the images during compression, thereby causing some problems. For example, some randomly distributed dotted noises may occur in the images during compression due to the fact that the DCT algorithm typically discards high frequency portions of images when processing images. Those noises caused by such a destructive compression algorithm are called mosquito noises.
Conventionally, mosquito noises in the image can be removed by the aid of related compression/decompression information generated during MPEG/JPEG compression. However, due to the variety of image media presently used in the market, it is often hard to know the origin of the image, and it is also hard for a back end device processing the image to get the related compression/decompression information. Thus, how to precisely remove mosquito noises from the image under such condition is certainly a tough issue.